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Environmental risks of polybrominated diphenyl ethers (PBDEs) in sewage sludge are assessed based on the concentration by exhaustive extraction, which is a likely overestimation of the pool available to exposed organisms. This study evaluated the bioaccessibility of PBDEs in sewage sludge from Shanghai using a 3-compartment model and a 6-d Tenax extraction. The very slowly fraction contributed 56-88% of total PBDEs in spiked sludge, whereas the rapidly desorbing fraction contributed only 1.1-10%. For the same PBDE congener, the rapidly desorbing fractions for sewage sludge measured in the present study were lower than those for sediment. The bioaccessible concentrations of PBDEs were 2.3-56 ng/g dry weight in sewage sludge from Shanghai, which represented 5.2% of the concentration determined by exhaustive (Soxhlet) extraction. BDE-209 was the predominant congener in sludge, contributing to 63% of the total. Moreover, the Ratio between 6-h Tenax and Soxhlet concentrations (T/S Ratio, indicating bioaccessibility) was lower in sludge generated from industrial wastewater treatment compared to sludge from facilities that treated mostly domestic wastewater. The T/S Ratio of PBDE congeners was related to KOW, specifically as KOW increases, the T/S Ratio decreased. These results will improve understanding of the fate and potential toxicity of PBDEs during land and/or landfill application of sewage sludge., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Sewage sludge is regarded as one important sink for hydrophobic pollutants, including hexabromocyclododecane (HBCD), but the current pollution situation of HBCD in sludge from China is unknown, despite that many studies have reported its occurrence in other environmental compartments across China. In this study, we collected 27 sludge samples from Shanghai to investigate the occurrence and distribution, to examine the diastereoisomer profile and sources, and to provide advice for future pollution control. HBCD is ubiquitous in sludge with a mean concentration of 4.7ngg(-1) dry weight (dw) (range: 0.10-37.2ngg(-1) dw), lower than data from European countries and the United States. Sludge from wastewater treatment plants (WWTPs) treating industrial wastewater contained high levels of HBCD. However, no significant relationships were found between HBCD and four parameters (total organic carbon, the percentage of industrial wastewater, capacity and sludge production of WWTPs). α- and γ-HBCD were two main components with the corresponding contributions of 47.9% and 48.0%. Comparing with the annual production of HBCD in China, its storage in sewage sludge is extremely low (less than 0.002%), indicating future release of HBCD from waste polystyrene foam will be significant, and careful considerations should be taken during waste disposal. To our knowledge, this is the first report on HBCD in sewage sludge from China., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Pharmaceuticals are heavily used to improve human and animal health, resulting in the frequent contamination of aquatic environments with pharmaceutical residues, which has raised considerable concern in recent years. When inadequately removed from drinking water in water treatment plants, pharmaceuticals can have potential toxic effects on human health. This study investigated the spatial distributions and seasonal variations of five pharmaceuticals, including ibuprofen (IBP), ketoprofen (KEP), naproxen (NPX), diclofenac (DFC), and clofibric acid (CA), in the Huangpu River system (a drinking water source for Shanghai) over a period of almost two years as well as the associated risk to human health for different age groups. All of the targets were ubiquitous in the river water, with levels decreasing in the following order: KEP (mean: 28.6 ng/L)≈IBP (23.3 ng/L)>DFC (13.6 ng/L)≈NPX (12.3 ng/L)>CA (1.6ng/L). The concentrations of all of the investigated compounds were at the low or medium end of the global range. The upstream tributaries contained lower IBP but higher NPX than did the mainstream and downstream tributaries. However, no significant variations were found in the levels of KEP, DFC, or CA at the different sampling sites. Except for CA in the mainstream, significantly higher pharmaceutical levels were observed in the dry season than in the wet season. Overall, a very low risk of the selected pharmaceuticals for human health via drinking water was observed, but future studies are needed to examine the fate and chronic effects of all pharmaceuticals in aquatic environments. To our knowledge, this is the first report to investigate the human health risk of pharmaceuticals in raw drinking water in China., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Wastewater treatment plants (WWTPs) are considered an important medium for the transport and transformation of organic pollutants, such as polybrominated diphenyl ethers (PBDEs) and dechlorane plus (DP). However, limited data on PBDEs and no data on DP were available regarding wastewater and sludge from China, especially in Shanghai, one of the most developed cities in China. This study examined the occurrence of PBDEs and DP in a conventional WWTP in Shanghai for one year. The levels of the total PBDEs in the influent and dewatered sludge ranged from 5.31 to 27.9 ng/L and 31.0 to 99.5 ng/g, respectively, which were at the low end of the global range. DP was reported in wastewater with a mean concentration of 0.46 ng/L (range: 0.05 to 1.40 ng/L) and sludge contained DP in the range of 1.1 to 2.0 ng/g. For both PBDEs and DP, there were no significant seasonal variations observed in the four seasons. Indoor dust and outdoor air could be two main sources of PBDEs and DP in the WWTP. In both the influent and sewage sludge, BDE-209 was the most abundant congener, with contributions to the total PBDE levels ranging from 52.9 to 82.6% and 82.7 to 84.0%, respectively. The fraction of anti-DP was consistently higher than that of syn-DP, and the average of fsyn ranged from 0.16 to 0.33, which fell in the range of two commercial DP mixtures. The annual releases of PBDEs and DP via sewage sludge from WWTPs in Shanghai were estimated to be 6,370 g and 164.8 g, respectively. The fate and risk of these compounds after being released into the environment require further research. To the best of our knowledge, this study is the first to report on the occurrence of DP in wastewater., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The concentrations of 19 polybrominated diphenyl ethers (PBDEs) congeners in a conventional wastewater treatment plant (WWTP) were determined to investigate the occurrence and fate of PBDEs during wastewater treatment processes. The level of total PBDEs ranged from 1.68 to 4.64 ng/L in wastewater, with BDE209 accounting for the largest proportion, followed by penta- and octa-BDE congeners. PBDEs were found to mainly exist in the particulate phase of wastewater, which rendered sedimentation efficient for the removal of PBDEs, while the removal efficiencies might be varied for congeners with different Br atom numbers. Because of similar congener profiles, in-house dust was considered to be an important source for PBDEs in the WWTP. According to the mass loading estimation, over 60% of total PBDEs entering the WWTP accumulated in the dewatered sludge, resulting in the total PBDE release of 43.8 kg/year via sewage sludge in Shanghai. And the annual release via effluent was estimated to be 5.5 kg, less but shouldn't be neglected., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Five PPCPs, including clofibric acid (CA), diclofenac (DFC), ibuprofen (IBP), ketoprofen (KEP), and naproxen (NPX) were selected as target compounds to investigate their occurrence and removal efficiency in a wastewater treatment plant (WWTP) of Shanghai. Furthermore, their distribution and potential toxicological risk in the WWTP receiving river water were investigated. The results showed that all targets were detected in WWTP influent, suggesting that domestic sewage discharge is an important source of PPCPs to the WWTP. Lower removal efficiency of these PPCPs was found in the WWTP and the main mechanism of elimination was biodegradation. The pattern of five selected PPCPs in the river was similar to that in WWTP effluent, indicating that WWTP effluent was a main source of PPCPs to the receiving water. Risk assessment showed that diclofenac posed a high risk, while ketoprofen, naproxen, clofibric acid and ibuprofen showed low risks to biota in the receiving river.

The occurrence and multi-phase distribution of five pharmaceutical compounds were investigated in an urban wastewater treatment plant (WWTP) receiving river by analysis of pharmaceuticals in sediment, particulate matter, conventional dissolved phase (>0.7 μm), colloidal phase (5 kDa to 0.7 μm), and truly dissolved phase (<5 kDa) water. Diclofenac was found in all samples, followed by clofibric acid, ibuprofen, ketoprofen, and naproxen with the decreasing detection frequency. All targets in WWTP outfall site were higher than those in the upstream and downstream, indicating that the WWTP is an important input source of pharmaceuticals in the river. The colloidal phase contributed 10-14% of ketoprofen, 8-26% of naproxen, 17-36% of clofibric acid, 22-33% of diclofenac, and 9-28% of ibuprofen in the aquatic system, suggesting the colloids will play an important role as carrier to contaminants in the aquatic environment. Based on truly dissolved concentrations of pharmaceuticals in water, only the risk quotient (RQ) value for diclofenac towards fish was higher than 1, indicating it poses a potential risk to aquatic organisms. Finally, a Level III fugacity model was used to further assess the environmental fate of the selected pharmaceuticals (exemplified for clofibric acid and diclofenac). Both clofibric acid and diclofenac tend to accumulate in water compartment with the percentage of 99.7% and 60.6%, respectively. Advection in river is a significant loss process for clofibric acid (56.4%) and diclofenac (54.4%)., (Copyright © 2013 Elsevier B.V. All rights reserved.)

The occurrence, behavior, and release of five acidic pharmaceuticals, including ibuprofen (IBP), naproxen (NPX), ketoprofen (KEP), diclofenac (DFC), and clofibric acid (CA), have been investigated along the different units in a tertiary-level domestic wastewater treatment plant (WWTP) in hyper-urbanization city of China (Shanghai). IBP was the most abundant chemicals among the measured in raw wastewater. The loads of the acidic pharmaceuticals in the WWTP influent ranged from 7.5 to 414 mg/day/1,000 inh, which were lower than those reported in the developed countries suggesting a less per capita consumption of pharmaceuticals in Shanghai. IBP obtained by highest removal (87 %); NPX and KEP were also significantly removed (69-76 %). However, DFC and CA were only moderately removed by 37-53 %, respectively. Biodegradation seemed to play a key role in the elimination of the studied pharmaceuticals except for DFC and CA. An annual release of acidic pharmaceuticals was estimated at 1,499 and 61.7 kg/year through wastewater and sludge, respectively, from Shanghai. Highest pharmaceuticals concentrations were detected in the effluent discharge point of the WWTP, indicating that WWTP effluent is the main source of the acidic pharmaceuticals to its receiving river. Preliminary results indicated that only DFC in river had a high risk to aquatic organisms. Nevertheless, the joint toxicity effects of these chemicals are needed to further investigate.

In order to study long-term effect of completely autotrophic nitrogen removal over nitrite (CANON) reactor, performance stability was investigated by using synthetic inorganic ammonia-rich wastewater as raw water with a continuous flow CANON reactor. Both performances of short-cut nitrification and ANAMMOX were stable for more than one year. Under the condition that inner temperature at 35 degrees C +/- 1 degrees C, pH 7.39 and 8.01, and hydraulic retention time 3.7-5.1 h, the average total nitrogen removal load was 1.8 kg x (m3 x d)(-1), and the average and maximum total nitrogen removal efficiency were 65.09% and 81.65% respectively. Under sudden low temperature conditions, both ANAMMOX bacteria and AOB were inhibited, however, the ANAMMOX bacteria were inhibited more, which caused highly accumulated nitrite. When temperature increased to 35 degrees C as normal, the performance of CANON reactor recovered soon, which means low temperature impact will have no significant influence on stability. When the temperature reached more than 50 degrees C, the activity of ANAMMOX bacteria was completely destroyed, so high temperature must be avoided, though AOB can recovered to normal in one week.